What color and how are zero, phase and ground wires indicated in an electrician? Wire color coding. What is wire color coding?

The color marking of wires is far from being an advertising "chip" of manufacturers, as some novice electricians believe. This is a special designation that allows the electrician to determine zero, ground and phase without the use of additional measuring instruments.

If the contacts are connected incorrectly, there may be backfire in the form of a short circuit and electric shock to a person.

The main purpose of color coding is to reduce the connection time of contacts and create safe conditions during electrical work. At the moment, in accordance with the PUE and European standards, each core has its own clearly defined color.

We will talk about the color of the neutral wire, grounding and phase.

Ground wire

By standards, the insulation of the "earth" is painted in a yellow-green hue. Some manufacturers apply yellow-green stripes to the ground conductor in the longitudinal and transverse directions. Rarely, but still found, shells of pure green or pure yellow color.

On electrical diagrams"earth" is denoted by two Latin letters "PE". Grounding is often called zero protection, but this is not a working zero, not to be confused.

Neutral wire

Both in a single-phase electrical network and in a three-phase one, the neutral is painted in blue or blue. On the wiring diagram, zero is indicated by the Latin letter "N". Neutral is also called zero or neutral working contact.

phase wire

This wire, depending on the manufacturer, is marked with the following colors:

white;
turquoise;
black;
brown;
pink;
red;
violet;
orange.

The most common phase colors are black, white and brown.

Despite the seeming simplicity, color coding It has a number of features that cause newbies to ask the following questions:

1.What is PEN?

2. How to determine the phase, grounding and zero if the insulation has a non-standard color or is completely colorless?

Let's deal with each point.

What is PEN?

The TN-C type grounding system, which is outdated today, assumes the combination of grounding and neutral. Its main advantage is the speed of electrical work. The disadvantage of TN-C is the high probability of electric shock during wiring in an apartment or house.

The main color for designating the combined wire is yellow-green, but at the ends of the insulation there is a blue color characteristic of the neutral wire.

On the wiring diagram, such a contact is indicated by three Latin letters "PEN".

How to find phase, ground and zero?

There are cases when, when repairing a household electrical network, it turns out that all conductors have the same color. In this case, how to determine which wire is which.

IN single-phase network, where there are only two wires, without grounding, you just need to have a special indicator screwdriver with you. First you need to turn off the electricity at the switchboard. Then the wires are stripped and bred to the sides. Now we turn on the electricity again and alternately bring the indicator to each of the wires. If, upon contact, the light on the screwdriver lights up, then this is a phase, and the second core, therefore, zero.

If electrical network three-phase, then you need more sophisticated equipment - a multimeter with measuring probes. First, set the device to a value above 220 volts. We fix one probe in phase, and the second we determine grounding and zero. Upon contact with zero, the tester should show a voltage of 220 volts. The ground wire will show a slightly lower voltage.

If you don’t have an indicator screwdriver or a multitester at hand, then you can determine the ownership of the wire by insulation. The important thing to know here is that the blue shell is always neutral. Even in the most non-standard markings, its color does not change. The other two cores are more difficult to install.

The first way is based on associations. For example, you have a colored and white or black contact in front of you. Usually the earth is indicated in white or black. Therefore, the remaining wire is a phase.

The second way. We discard the neutral again. Left red and black. According to the PUE, white insulation is a phase. Then the red conductor is ground.

In circuits with direct current, the color marking of minus and plus is represented by black and red insulation, respectively. In a three-phase transformer network, each phase is painted in an individual color:

A-yellow;
B-green;
S-red.

Zero, as always, is blue, and ground is yellow-green. In cables designed for a voltage of 380 volts, the wires are designated as follows:

A-white;
B-black;
S-red.

The protective and neutral conductors do not differ in marking from the previous version.

We designate the wires ourselves

In the absence of a visual indication, after repair work you need to specify the ownership of the wires yourself. For this, bright electrical tape or heat shrink tubing is suitable.

According to GOST, the marking of the cores must be carried out at the ends of the conductors - at the points of their contact with the bus.

These notes will make it much easier. future renovation and service.

Content:

Many, when purchasing electrical wiring, do not even pay attention to the color of the insulation of the cores themselves. It seems to them that it is more profitable for an apartment to purchase an ordinary white product, without external insulation - because it is cheaper. But this is fundamentally wrong, because the color marking of the veins does not exist for beauty. Rather, the coloring of the insulation is a necessity dictated by safety and convenience.

For example, if the wiring was installed in accordance with the color marking of the cores, then in order to understand where the phase wire is, and where zero or ground is, a quick glance is enough, since there are not too many of them and it is easy to remember them.

The designations of wires by color, in addition to ease of installation, also ensure the safety of the electrician. After all, looking at the wire, you can already understand whether it is necessary to remove the voltage for repairs, or you can do without it.

Now let's try to understand what color the wires of the zero and ground phases are and how this can help in the work of not only an electrician, but also a home master.

What color is the ground wire?

The color of the ground wire, according to the European standard, is yellow with a green stripe. But in domestic veins, it can be solid yellow or solid light green. Here the designation by color plays very important role. The fact is that, provided that a residual current device (RCD) is installed in the power cabinet, from where the power is supplied to the room, then if you confuse the ground wire with zero, it will permanently turn off.

It makes sense to consider an example. A three-core automatic reclosure, popularly referred to as "noodles", comes from underground in a pipe. It is unrealistic for an electrician to understand which of the cores is zero and which is grounding, since both of them behave the same during testing. When connecting one contact of the control lamp to the phase, and the second to the ground wire, it will glow in the same way as when connected to the phase and zero.

This is the plus of a separate color marking of the ground wire. If in the same situation AVVG will come, for example, 3x2.5 (that is, a three-core cable with a cross section of 2.5 sq. mm), the electrician will not even have to get a test lamp or a multimeter (although you still need to check, because it is not known who and How did you connect). Everything will be clear by the colors, where is the ground of what color is the phase wire and so on. If the wire is yellow-green, then, subject to proper connection, it will be grounding.

Neutral wire in marked cable

The color marking of the neutral core in the cable is indicated by blue or light blue. There are also options white color insulation with a blue stripe, or a blue core with a white stripe. Schematic marking - "N", that is, neutral.

Also when installing blue wire or insulation of complementary colors do not come to switches or other breakers. They go from junction box directly to the lamp.

In distribution power boards, the incoming neutral wire comes to the neutral bus either directly, or through the machine, or from the meter. Further, all blue and blue wires are connected to the same bus. blue flowers from outgoing cables.

Of course, if the wiring was done by other people, you cannot fully rely on their attentiveness - as they say, trust, but verify. Therefore, you should check with the indicator whether there is voltage on this wire. But already in the apartment or in the room where the wiring was installed personally, such questions will not arise.

phase wire color

The color of the phase is represented by a wider range. The thing is that at a voltage of 380 volts, there are three opposite phases in the cable. And if there is a short circuit between them, that is, a short circuit of the phase voltage is much more dangerous than a short circuit of the linear voltage (phase wires with zero).

The color of the phase wires can be as follows: black, red, brown, gray, purple, pink, white, orange and turquoise color. In fact, it is necessary to remember only three colors in such markings. These are the colors that indicate the ground and zero, that is, the neutral wire. All other colors will be phase, that is, carrying a dangerous voltage.

And if suddenly mixed colors come to the introductory machine, then it is better to stick to the correct ones during further installation - you should not hope that the wrong colors are deposited in the memory. The best option would be in which further wiring will proceed in accordance with safety regulations. This will protect you from damage. electric shock when the phase wire comes into contact with the body (after all, the voltage of 220 volts is life-threatening, not to mention 380) and short circuits during subsequent additions of cables or revisions of the electrical installation of the apartment.

An interesting fact is that the color marking of non-insulated power buses in transformer and other power plants is slightly different from the marking of insulated wires. So, in the presence of three phases:

Phase A - yellow;
Phase B - green;
Phase C is red.

D.C

Of course, everyone is used to the fact that alternating current flows in the supply network of the apartment, but when installing networks direct current there are rules that govern the color marking of wires.

It is well known that there are no “phases” and “zero” in electrical wiring of this type. In this two-wire system, only "minus" and "plus" are present. The generally accepted color is a red “plus” wire and a blue “minus” wire. Sometimes a third light blue wire may be present. This will be the zero "M" contact. Provided that a cable with three cores and a cable with two are connected, the contact “M” that goes with “minus” and “plus” is excluded, and the rest are connected exclusively in accordance with the color.

Of course, in an apartment with such wiring you can only encounter during installation LED backlight, but still this information will not be superfluous.

What to do with incorrect labeling

Of course, if it is necessary to carry out wiring repairs or additional connections, it often happens that the marking of the cores does not comply with the rules. In this case, you need to stock up on colored electrical tape and, after ringing all the wires with a multimeter, mark in the immediate vicinity of the connection in order to subsequently understand what charge the line in front of your eyes carries. Knowing its purpose, there will be no need to call. Of course, it is not so easy to distinguish the neutral wire from grounding, but this is also possible.

Having found the phase wire with a screwdriver of the indicator and marking it with the desired color of electrical tape, you need to switch to working with a multimeter. By measuring the voltage alternately on the conductors, together with the phase, it is necessary to determine the deviations. The voltage between the phase and neutral core will always be higher than between the phase and ground.

By the way, for marking the ground wire for sale on the shelves of electrical stores, there is precisely yellow-green electrical tape. It will replace the yellow-green wire in the circuit.

Afterword

If it suddenly turned out that during installation a violation of color marking was noticed, there is no need to repeat other people's mistakes and continue wiring not according to the established rules. It is better to correctly mark the incoming veins, and then lead it according to the necessary colors. This method will save, subsequently, from the troubles and inconveniences associated with the revision, repair of wiring in the apartment and will significantly reduce the time spent on these actions. After all, it is much more convenient when the fitter knows what this or that designation means and is sure that you can not be afraid of the colors meaning grounding and zero, but you should be more careful with the red wire.

Today, it is unthinkable to install an electrical cable without the use of wires in colored insulation. Such marking of conductors is an urgent need, since by indicating the purpose of each wire, it helps to reduce the likelihood of errors during installation and, as a result, the occurrence of a short circuit.

Before you deal with the decoding of the markings, it is recommended that you familiarize yourself with the parameters by which the wires are separated:

Number of cores. Depending on this parameter, the cable can be used to ensure the operation of electric motors, for wiring in a house or apartment, for transmitting current in power networks.
Conductor material. As a material in electrical most commonly used copper and aluminum or a combination of these metals.
Insulation. Wires can be with or without insulation. Bare conductors provide a connection for power lines. Insulated are laid in places where there is a possibility of exposure to them external factors in the form of wind, water, dust or snow. Plastic, rubber, lead, paper and many other materials are used as insulation.
Cable section. With this indicator you can determine the strength of alternating or direct current, which will pass through the conductors.
Other indicators. Resistance, power and voltage indicators are very important for network wiring and connecting various devices.

Knowing which conductors are responsible for the loads, you can correctly connect to the meter, repair the wiring, connect the oxygen sensor in the car, etc.

Wire marking for three-phase alternating current

By looking at the color marking, you can easily determine the ground, zero and phase. In modern electrical conductors each vein has an individual color. Knowing which core corresponds to which color, installation can be easily carried out. If the installation was carried out with new wiring and according to modern standards and rules, then this is quite enough.

Neutral or working zero is blue or blue-white.
Grounding or protective zero is a yellow-green wire.
The phase can be marked with all other colors, including:

turquoise;
orange;
white;
pink;
violet;
grey;
red;
brown;
black.

Having dealt with the color of the marking, you can easily determine which wire is responsible for which function. Due to a different scheme of work, an exception may be conductors suitable for switches, switches, etc.

Color of wires plus (+) and minus (-) in DC networks

In some areas in the national economy, DC networks are used:

for operational circuits of protection and power supply of automation at electrical substations;
in electrified transport;
in construction, industry, when storing materials.

In such networks, only two conductors are used: positive and negative buses. Phase or zero conductor they don't have.

Marking of wires and tires for DC networks:

red is used for positive charge wires;
blue - for tires and wires with a negative charge;
the middle conductor is indicated in blue.

If the DC network is created from a three-wire network (by branching), then the color of the positive conductor is the same as the positive conductor of the three-wire circuit.

Wire colors in electrical wiring

The designation of wires by color is very convenient, especially when one person does their laying and connection, and another will service and repair.

Every the color of the conductor determines its purpose in a cable according to a certain standard, which has been changed several times since the times of the USSR.

Today, conductors in electrical installations alternating current with a dead-earthed neutral and voltages up to a thousand volts have a very specific marking.

Color of zero working and zero protective wires

Zero working conductors are indicated in blue.
Zero protective ones are painted in yellow-green transverse or longitudinal stripes.
Combined zero protective and zero working conductor along its entire length marked in blue with yellow-green stripes at the connection points. It may be the other way around - the entire conductor is yellow-green, and the junctions are colored blue.

This combination of colors is used only for marking zero protective pinching conductors.

How to independently determine the ground, zero and phase of the wires if there is no marking?

Quite often, situations arise when the connection is made incomprehensibly how. Some electricians, even today, may be using outdated wiring codes, leaving others to look for zero and phase with a probe and mark the conductors of the desired color with electrical tape or heat shrink tubing of the desired color.

Phase detection with an indicator screwdriver

Inside the probe is a resistor and a lamp. When the tip of the screwdriver touches the contact and the live conductor, the circuit closes and the lamp lights up. The resistance reduces the current to a minimum, protecting against electric shock. Thus, it is quite easy to find out which phase wire is.

This is the most preferred option for determining the phase, especially since the cost of a screwdriver is quite affordable. Its main drawback is the possibility of erroneous operation. Sometimes indicator screwdriver can react to pickups and to determine the presence of tension where it is not.

Determination of ground, zero and phase using a test lamp

This method of determination is quite effective, but requires special care:

a lamp is screwed into the cartridge, and wires with insulation removed at the ends are fixed to its terminals;
you can also use the usual table lamp with electric plug;
The technology is quite simple lamp wires are alternately connected to the conductors that need to be defined.

In this way, you can only find out in which conductor there is a phase. If the control lamp lights up, then this wire has a phase. If the lamp does not light, then there is no phase among the wires or there is no zero. This also cannot be ruled out.

To determine the phase wire, one of the ends coming from the lamp can be connected to a known zero, and then when the second end is connected to the phase conductor, the lamp will light up. The wire that will remain and will be zero, respectively.

The way to determine the phase or zero using a lamp is good for checking the health of the wiring.

It should be remembered that when working with electrical wires, care and caution are required.

Those who have dealt with electrical wires at least once in their lives could not help but pay attention to the fact that cables always have a different color of insulation. It was not invented for beauty and bright colors. Thanks to color scheme in wire clothes it is easier to recognize phases, grounding and neutral wire. All of them have their own color, which many times makes it convenient and safe work with electrical wiring. The most important thing for the master is to know which wire should be indicated by which color.

Wire color coding

When working with electrical wiring, the wires to which the phase is connected are the most dangerous. Contact with the phase can be fatal, so the brightest warning colors, such as red, are chosen for these electrical wires.

In addition, if the wires are marked with different colors, then when repairing a particular part, you can quickly determine which of the wire bundle needs to be checked first and which of them are the most dangerous.

Most often, the following colors are used for phase wires:

Red;
Black;
Brown;
orange;
Lilac,
Pink;
purple;
White;
Grey.

It is in these colors that the phase wires can be painted. You can deal with them easier if you exclude the neutral wire and ground. For convenience, it is customary to designate the image of a phase wire in the diagram with the Latin letter L. If there is not one phase, but several, a numerical designation should be added to the letter, which looks like this: L1, L2 and L3, for three-phase networks in 380 V. In some versions, the first phase (mass) can be indicated by the letter A, the second - B, and already the third - C.

What color is the ground wire?

In accordance with modern standards, the ground conductor should be yellow-green. In appearance, it looks like yellow insulation, on which there are two longitudinal bright green stripes. But sometimes there is also a color of transverse green-yellow stripes.

Sometimes, the cable may only have bright green or yellow conductors. In this case, the "earth" will be indicated in this color. It will also be displayed in the corresponding colors on the diagrams. Most often, engineers draw from bright green, but sometimes you can see yellow conductors. They designate “earth” on diagrams or devices in Latin (in English) letters PE. Accordingly, the contacts where the "ground" wire must be connected are also marked.

Sometimes experts call the ground wire "zero and protective", but do not confuse. If you see such a designation, then know that this is exactly the earth wire, and it is called protective because it reduces the risk of electric shock.

Zero or neutral wire has the following marking color:

Blue;
Blue;
Blue with white stripe.

No colors are used in electrics to mark the neutral wire. So you will find it in any, whether it is three-core, five-core, and maybe with even more conductors. Blue and its shades are usually used to draw "zero" on various schemes. Professionals call it a working zero, because (which cannot be said about grounding), it is involved in electrical wiring with power. Some, when reading the diagram, call it a minus, while everyone considers the phase a “plus”.

How to check wire connection by color

Wire colors in electricity are designed to speed up the identification of conductors. However, relying only on the color is dangerous, because some novice, or an irresponsible worker from ZhZK, could connect them incorrectly. In this regard, before starting work, it is necessary to make sure that they are labeled or connected correctly.

In order to check the wires for polarity, we take an indicator screwdriver or a multimeter. It is worth noting that it is much easier to work with a screwdriver: when you touch the phase, the LED built into the housing lights up.

If the cable is two-core, then there are practically no problems - you have excluded the phase, which means the second conductor that remains is zero. However, three-core wires are also common. Here, to determine, you will need a tester, or a multimeter. With their help, it is also not difficult to determine which wires are phase (positive) and which are zero.

This is done as follows:

The switch is set on the device in such a way as to select a jackal of more than 220 V.
Then you need to pick up two probes, and holding them by plastic handles, very carefully touch the rod of one of the probes to the found wire-phase, and lean the second to the supposed zero.
After that, 220 V, or the voltage that is actually in the network, should be displayed on the screen. Today it may be lower.

If the display shows 220 V or something in this limit, then the other wire is zero, and the remaining one is presumably ground. If the value that appears on the display is less, it is worth continuing the test. With one probe we again touch the phase, with the other to the intended ground. If the readings of the device are lower than in the case of the first measurement, then you have a "ground". By standards, it should be green or yellow. If suddenly the readings turned out to be higher, this means that they messed up somewhere, and you have a “zero” wire in front of you. The way out of this situation is either to look for exactly where the wires were connected incorrectly, or to leave everything as it is, remembering that the wires are mixed up.

Wire designations in electrical diagrams: connection features

Starting any electric installation work on lines where the network has already been laid, you must make sure that the wires are connected correctly. This is done with the help of special testing devices.

It must be remembered that when checking the phase-zero connection, the readings of the indicator multimeter will always be higher than in the case of continuity of the phase-to-ground pair.

Wires in electrical circuits are color-coded according to standards. This fact allows an electrician to find zero, ground and phase in a short period of time. If these wires are connected incorrectly to each other, a short circuit will occur. Sometimes such an oversight leads to the fact that a person receives an electric shock. Therefore, it is impossible to neglect the rules (PUE) of connection, and you need to know that the special color marking of wires is designed to ensure safety when working with electrical wiring. In addition, this systematization significantly reduces the work time of an electrician, as he has the ability to quickly find the contacts he needs.

Features of working with electrical wires of different colors:

If you need to install a new one, or replace an old outlet, then it is not necessary to determine the phase. It doesn't matter to the plug which side you plug it in.
In the case when you connect a switch from a chandelier, you need to know that it needs to be supplied with a specific phase, and only zero to the bulbs.
If the color of the contacts and the phase and zero are exactly the same, then the value of the conductors is determined using an indicator screwdriver, where the handle is made of transparent plastic with a diode inside.
Before defining a conductor, electrical circuit in a house or other room it is necessary to de-energize, and the wiring at the ends to be cleaned and parted to the sides. If this is not done, then they may accidentally touch and a short circuit will result.

The use of color coding in electrical engineering has made life much easier for people. In addition, thanks to color coding, high level increased safety when working with wires that are energized.

Designations and colors of wires in electrics (video)

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In modern life, marking wires by color is not a manufacturer's advertising move to stand out from others. This is a necessity and requirement, without which fast and high-quality installation of electrical wiring is impossible. How does this color help?

quick identification of the purpose of the wire (phase, zero or earth)
reduction in the number of erroneous connections during installation
no need for wire continuity for phasing

Manufacturers choose the colors of the conductor not at will, but according to the rules. Moreover, not only color can be applied to the conductor, but also digital letter designation.

The coloring is applied along the entire length of the core insulation. But in some areas, you can also use multi-colored cambric for heat shrink. Basically, they are widely used in cable terminations.

Coloring in the network 220V and 380V single-phase and three-phase voltage

In a three-phase network, wires and buses were previously painted as follows:

Yellow color

Green color

Of red color

In order to make it easier to remember the order of colors, electricians used the abbreviation - J-Z-K.

Since 01/01/2011, new standards have been introduced in accordance with GOST R 50462-2009 ():

Brown

Now it's time to switch to abbreviations - K-Ch-S! Subjectively speaking, this marking loses in clarity to the previous coloring of Zh-Z-K.

And imagine that in a switchboard or indoors bad light, dust on the wires? What do you think your eye is better at distinguishing yellow from green or brown from black? In this case, the rules stipulate the need for letter designation and marking of cores, in addition to color.

Letter designation of wires

What should be the letter designation of wires according to GOST is presented in the following tables:

It is best to apply these letters with the help of special rings of tags.

They are a PVC tube, pre-cut, with letters and numbers printed on it.

Mark phase conductors yellow or in green prohibited under the new rules. It is because of their similarity with the yellow-green ground conductor.

It is also worth pointing out that the brown color is exactly phase A or L1 (just L in a single-phase 220V network), and black is phase B or L2. When you are wiring for yourself, you may unwittingly miss this moment. But if the electrician is done on industrial facility, then here you will be required to strictly comply with the international standard and correct phasing.

White color is the cheapest option in the manufacture of core insulation, as it does not require the use of dyes. Therefore, it is most often used by manufacturers of cheap brands of cables. There are no special marking instructions for this color.

Online coloring constant voltage

3 buses are involved in DC voltage networks. There is no zero and phase familiar to us. There is a positive conductor or bus (with a plus sign) and a negative conductor (with a minus sign). The plus tire, according to the old rules, should be red, the minus one should be blue. Zero working tire - blue.

According to the new standards from 01.01.2011:

Plus

Brown

Minus

gray color

Middle conductor

Of blue color

Errors and color options for phase, neutral and ground wires

The issue of marking wires by color arises sharply when one electrician installs the wiring and then serves another. Subject to all the rules of coloring, troubleshooting saves both time and money.

Unfortunately, in the old Soviet wiring, most of the conductors are monochrome, and here you can’t do without a probe or multimeter.

If there is a color marking and observed, then the neutral and protective wires must be:

Neutral wire N - must be blue.
Zero protective PE - yellow-green.
The conductor combining zero protective and working zero PEN is yellow-green along the entire length of the wire, but at the end at the junction it is blue.

When coloring the phase wires, the manufacturer is given a choice from a variety of color options. Here are the main ones:

Custom wire colors

Sometimes, due to incorrect labeling of colors by manufacturers, one has to neglect GOST. For example, you have 3 cores in a cable of different colors:

blue
brown
black

In this case, you do the phase according to the rules, namely, in brown. The neutral wire will be blue. But the black core will become grounding. In this version, the colors will at least resemble the Soviet standard.

Another of the “inconvenient” options for combining the colors of the cable cores:

black
blue
red

In order to violate GOST to a minimum and be close to its requirements, make the phase black. Blue is zero, but red will be the protective conductor PE.

Just be sure to mark it at the end with yellow and green electrical tape.

But what if there is not a single color resembling a phase wire in the cable at all? That is, the colors black, brown and gray are missing. Then choose for the phase the wire that matches as closely as possible to established by the rules brown. For example, red.

Even at the ends of the wire cutting, according to the phasing, you can put on multi-colored insulating thermotubes or multi-colored electrical tape.
In order not to resort to such methods, pay attention to its color in advance at the stage of buying and choosing a cable.

What to do if the cable is already laid without color marking?

Most often, you may encounter a situation where the wiring has already been laid, and the electrician who did this, as a rule, did not bother to familiarize himself with the rules for color marking and GOST. What to do in this case?

There is nothing left to do but pick up devices - a probe, an indicator, a dial tone and waste time looking for the necessary conductors.
After each definition of one or another conductor, use colored tubes to designate them according to GOST and proceed to the next one. It is enough to make this designation only at the end and beginning of the cable, and not along its entire length.

Phase conductors from zero are easy to distinguish. And how to distinguish a zero worker from a protective one can be found in the article "".

Wire color tips to follow during installation:

try not to use cables from different manufacturers. As a rule, their colors are not the same, which in the future can lead to errors during installation.
if you still have to work with cables of different manufacturers and colors, at the very beginning, call all the cores and mark them in advance with multi-colored electrical tape so as not to confuse them in the future. Don't rely on your memory
when you have to build a short cable, then use wires of the same colors as in the main section.
try not to use cables that do not have yellow-green cores (protective zero)
if the cable does not have a yellow-green core, then use the nearest related color as the ground.